lolol, then they have a disability which makes them eligible to benefit from all the provisions and accommodations applicable to the Americans with Disabilities Act.
Ah! So Marty is attempting to reason that because Gay people don't have sex with people of the other sex (most of them do or at least have btw) they are biologically inferior to straights? If so, we've been down this rabbit hole with him before.
Anything that leads you to be less likely to pass your DNA down to future generations is biologically "bad". Not wanting to have sex with members of the opposite sex in a species that uses sexual reproduction makes you less likely to pass down your DNA.
Just like my nearsightedness makes me less likely to survive too long and pass on my DNA if I didn't have access to the technology of corrective lenses.
This has nothing to do with morality, just straight biology.